It is interesting to think that societies would not only (forcibly) include specialized individuals necessary for civilization in frontline combat but also provide them with little training, equipment, or screening for aptitude. If i were to set aside my own opinions about war and forcing people to participate in it, it would simply be wiser to not only have a specialized class of soldiers, but to also eliminate individuals not suited to the task. Militaries into the modern era also have the issue through nepotism in the officer corps and incentivising the most impoverished to join the enlisted, they have the benefit of significantly larger numbers (total population), mechinization, and long range engagement. Even the most catastrophic combat in the modern era does not have the same (immediate) death toll.